Boy were we shocked when we got our ﬁrst energy bill in the winter of 2010! Turns out, trying to keep a drafty house warm is a rather expensive endeavor (and, as you may recall, our ﬂoors aren’t insulated). We have been engaged in a number of experiments to keep energy costs down and the task recently became much easier when we signed up for Entergy’s In-Home Display pilot program. We now have a small meter that lets us know when we have spikes in energy consumption (driven, not surprisingly, by HVAC dependency).
We’ve had to adjust our expectations when it comes to comfort level: no longer do we submit to the standard operating temperature of 68 degrees, year round. In the winter, we get used to being a little more chilly and keep the house at around 65 degrees (and supplement with a space heater as needed). In the summer, we get used to being a little more warm and keep the house at around 78 degrees (and ditch the down comforter).
We also follow these useful tips:
- Keep TV, stereo, DVD player and gaming devices plugged into one power strip and turn the power strip on and off with use (you may be familiar with the term “vampire appliances”).
- Routinely change air ﬁlters.
- Adjust water heater temperature to 120 degrees.
What are some ways you stay comfortable and save energy at the same time? Cooling season is upon us! Send me your suggestions and I’ll follow up with the next Monthly Spectator!
This month, I’m turning my attention to a more ‘global’ observation !
In November, I had the great fortune of traveling to South Africa for vacation and, while there, had the opportunity to visit a hugely growing yet terribly impoverished community on the outskirts of Cape Town. It was an incredible glimpse not only into the culture and history of Cape Town but also a reminder that there were probably many, many communities such as this one at some point in the history of developing cities in the United States.
What made my experience unique was the realization that I was witnessing a very modern phenomenon in that a poor, underdeveloped community has rapidly growing access to global technologies (something that I doubt existed decades ago).
As a ‘for instance,’ this community has not, and never will be, introduced to what we know as “land lines” for telephone communication: this community leapt straight in the realm of cellular technology. Cellular technology is just more economical.
On top of this, the community is also leaping directly to solar-powered technology and foregoing what we know to be the conventional use of electric-powered or gas-powered home appliances. Inexpensive and highly efﬁcient solar water heaters decorate the rooftops of many homes that otherwise appear to be lacking in ammenities.
I had to ask myself; Why aren’t we doing more of this?
A recent study by the Earth Policy Institute reveals that the U.S. “ranks 36th in installed [solar water heater] capacity relative to its population.” Food for thought the next time you enjoy a nice, hot shower!
Since I wrote about my drafty home in last month’s post, I’ve gotten a few requests to talk about the measures I’m taking to improve energy efﬁciency! You may recall that our energy consultant was unable to establish a pressure differential in our house such that an effective measurement of air ﬂow could be taken. What I didn’t mention is that while the consultant was performing her blower door test, we walked around the house and felt wind (yes, wind) coming through just about every little hole and ﬁssure in the house. Not surprisingly, it was recommended that we seal just about every little hole and ﬁssure in hopes that less energy would, literally, get thrown out the window. These include:
- Gaps between window frames and window units.
- Holes in the mortar joints in our ﬁ replace(s).
- Gaps between electrical junction boxes and drywall.
- Gaps between plumbing piping and drywall and/or gaps between plumbing piping and the ﬂoor.
Lack of proper weatherstripping was a key factor in the blower door test failure; many of the double hung windows have large gaps between the upper and lower sashes and the wood has shrunken to such a degree that the sashes just aren’t tight ﬁts. A great resource for retroﬁt weatherstripping can found be found by going to page 70 in this PDF.
Additionally, because one can see daylight through some of the cracks in our wood ﬂoors, it was recommended that we insulate either by way of spray foam between ﬂoor joists or by securing rigid insulation, continuously, across the bottom of all the ﬂoor joists (the latter accouting for thermal breaks and ease of installation).
Needless to say, I’ve been doing lots of climbing on ladders and lots of poking and prodding. Turns out, there is an art to installing spray foam sealant and a variety of brands and types with which to experiment (some expanding far more than others). That said, I would be remiss if I didn’t mention that there is another art to energy savings: Spend less on cooling your home by not setting the thermostat so low!
My personal preference is DAPTex.
When we bought it at the end of 2009, my husband and I quickly noticed that the house was… shall we say… drafty. Having lived in a home that was built over a hundred years ago, I knew not to expect modern-day comfort but this was a whole different story. So, in anticipation of making some “energy improvements” on the house, we enlisted the help of an energy auditor to perform a “blower door test” (see image below). The results? Drafty was an understatement.
Blower door tests require that a house be de-pressurized to a difference of, say, 50 Pascal before beginning to measure either the air ﬂow required to achieve that 50 Pascal or the number air exchanges per hour. Our auditor could not even get a reading of 50 Pascal to begin with (read, our house does little more than keep the rain out). It was an eye opening experience to say the least and I’m glad to have observed the process… it is one that I think the entire construction industry will have to familiarize itself with in the very near future.
I say that because the “topic du jour” at this year’s CSI Convention was ‘high performance building’ and the looming possibility that the International Green Construction Code will be adopted as code in many municipalities (already adopted in Rhode Island!).
As is currently the case under some States’ energy codes (mostly up North) or by some green building standards, the air ﬂow rate per square foot of a building must be range from 1 to 1.5 cfm/ft2. If the IGCC is adopted (which references ASHRAE 189.1), the required air ﬂow rate will be 0.4 cfm/ft2 (at 75 Pa) and building envelope commissioning (energy auditing) will be required! So, maybe it wouldn’t hurt to start getting those ﬂashing, penetration and transition details in order and update your air barrier spec!
My husband and I purchased a home here in New Orleans – one that was renovated in 2002 and, fortunately, relatively unaffected by Hurricane Katrina. It is our ﬁrst home and the degree of maintenance, as I’m sure most of you can imagine, is fairly high. As I continue to poke around and get a better understanding of construction and installation methods, I am amazed: I’ve gone through more expanding foam sealant in the past few months than I care to admit! We had an energy audit done on the home and the result of the blower door test was such that no baseline could properly be established: we could feel air ﬂowing through holes in the brick ﬁreplace mortar! This made me wonder where else there might be a “breach” in the exterior envelope’s air tightness only to learn that there is no exterior sheathing on the house! In talking with a co-worker, I was introduced to an interesting concept in old home retroﬁtting – an except of which is below… (improved image coming soon)